The width the output pulses shown are modulated
236 Chapter Thirteen
| 13.6.2 | ||
|---|---|---|
Figure 13.19 PWM signal to give a 1 kHz sine wave using positive and negative supplies.
13.7.1 Width modulation
Width coded signals or PWM are blocks of RF energy whose width is proportional to the amplitude of the instrumentation data. Upon reception the width can be accurately measured and the amplitude of the instrumentation signal recon-stituted. Figure 13.20a shows the relation between the voltage amplitude of the instrumentation signal and the width of the transmitted pulses, when trans-mitting a series of 1 V signals and a series of voltages through 10 V.
